CN115193600A

CN115193600A - Injection device, method of manufacturing injection head, and method of improving fluid plume characteristics

Info

Publication number: CN115193600A
Application number: CN202210320077.1A
Authority: CN
Inventors: 麦可·A·马拉三世
Original assignee: Funai Electric Co Ltd
Current assignee: Funai Electric Co Ltd
Priority date: 2021-04-08
Filing date: 2022-03-29
Publication date: 2022-10-18
Also published as: US20230364625A1; EP4285972A2; JP2022161864A; EP4070958B1; US20220323973A1; EP4285972A3; EP4070958A1

Abstract

A fluid jet ejection device, a method of manufacturing an ejection head, and a method for improving a plume characteristic of a fluid ejected from the fluid jet ejection head are applicable to a variety of fluids having different fluid characteristics. The fluid jet spray device includes a cartridge body and a fluid jet spray cartridge disposed in the cartridge body. The fluid jet ejection cartridge includes a fluid and an ejection head attached to the fluid jet ejection cartridge. The ejection head includes a plurality of fluid ejectors on the ejection head and a nozzle plate having a plurality of fluid ejection nozzles therein associated with the plurality of fluid ejectors, wherein a first portion of the plurality of fluid ejection nozzles have a first axial flow path length and a second portion of the plurality of fluid ejection nozzles have a second axial flow path length greater than the first axial flow path length.

Description

Injection device, method of manufacturing injection head, and method of improving fluid plume characteristics

Technical Field

The present disclosure relates to fluid jet ejection devices for transporting fluid droplets (fluid mist droplets) therefrom, and in particular to modified fluid jet plume characteristics for fluid jet ejection devices, and more particularly to a fluid jet ejection device, a method of manufacturing an ejection head, and a method of improving fluid plume characteristics.

Background

Fluid ejection devices have been designed and used to eject ink onto a substrate. However, new uses for fluid ejection devices continue to develop. For example, fluid ejection devices may be used for vapor generation devices for drug delivery (e.g., nasal, oral, lung, eye, and wound care applications), as well as for ejecting various non-aqueous fluids (e.g., lubricants and fragrances). Many of the aforementioned applications require the ejection of a mist of liquid droplets from a fluid ejection device. However, conventional fluid ejection devices are designed to eject fluid droplets in a straight line toward a substrate. The use of a fluid ejection device to provide a mist of fluid droplets is contrary to the design of conventional fluid ejection devices.

For example, nasal spray devices provide a fluid mist that is injected into the nasal cavity. Nasal spray devices have become an important method of delivering drugs to patients. Such devices are more convenient to use than administration by Intravenous (IV) or injection. Spray devices also provide higher bioavailability of the drug compared to oral administration. Absorption of the drug by the spray device is faster than absorption by oral administration, since the drug delivered by the nasal spray device is directed into the bloodstream so that the effect of the drug is more direct.

Fig. 1 is a cross-sectional view (not to scale) of the anatomy of a human nasal cavity 10. A portion of brain 12 is shown above nasal cavity 10. The olfactory bulb 14 is disposed between the brain 12 and the lamina cribrosa 16. The olfactory mucosa 18 is located below the cribriform plate 16. The nasal cavity also includes an upper turbinate 20, a middle turbinate 22, a respiratory mucosa 24, and a lower turbinate 26. Item 28 represents the palate. The pharmaceutical mist is injected through the nostrils 30 and the squamous mucosa 32 into the nasal cavity 10. In order to achieve proper delivery of the drug to the bloodstream using a nasal spray device, the drug must be delivered to the highly vascularized respiratory mucosa 24. Two areas that are highly vascularized are the olfactory and respiratory regions. The respiratory region contains the nasal concha, which increases the surface area for drug absorption.

It is believed that smaller, lower velocity fluid droplets are most beneficial for deposition of the drug in the nasal cavity 10. Fluid droplets with high inertia will tend to land in a straight line motion and only at the point at which they are aimed. Fluid droplets with low inertia will be affected by air resistance and air flow and are more likely to float throughout the nasal cavity for more uniform drug delivery coverage.

Another aspect of spray devices for delivering drugs that may increase deposition coverage is the Plume Angle (PA) of the fluid droplets. Wider plume angles are believed to provide greater fog formation and thus better drug delivery coverage. Traditional methods for delivering medication via the nasal cavity include medication pipettes, multiple spray bottles with spray tips, single dose syringes with spray tips, and dry powder systems. As a result, conventional drug delivery devices are typically designed to deliver a specific drug to the nasal cavity, and each device may not be suitable for delivering a wide range of drugs via the nasal route. Many conventional methods for nasal drug delivery rely on a pressurized reservoir to inject a mist of fluid into the nasal cavity. Thus, drug delivery devices are typically designed for a specific drug and may not be suitable for administering different drugs.

While a variety of devices for delivering fluid mist are available, there remains a need for a fluid mist ejection device that can be fine tuned to deliver a variety of fluids over a range of velocities, fluid ejection times, and plume angles.

Disclosure of Invention

In view of the foregoing, embodiments of the present disclosure provide a fluid jet ejection device, a method of manufacturing an ejection head, and a method for improving plume characteristics of fluid ejected from the fluid jet ejection head. The fluid jet spray device includes a cartridge body and a fluid jet spray cartridge disposed in the cartridge body. The fluid jet ejection cartridge includes a fluid and an ejection head attached to the fluid jet ejection cartridge. The ejection head includes a plurality of fluid ejectors on the ejection head and a nozzle plate having a plurality of fluid ejection nozzles therein associated with the plurality of fluid ejectors, wherein a first portion of the plurality of fluid ejection nozzles have a first axial flow path length and a second portion of the plurality of fluid ejection nozzles have a second axial flow path length greater than the first axial flow path length.

In another embodiment, a method of manufacturing an ejection head is provided. The method of manufacturing an ejection head includes: a semiconductor substrate having a plurality of fluid ejectors thereon is provided. A fluid flow layer is applied to the semiconductor substrate. Imaging and developing fluid channels and fluid chambers in the fluid flow layer. A fluid supply via is etched through the semiconductor substrate. Applying a first nozzle plate layer to the fluid flow layer. Imaging and developing the first nozzle plate layer to provide a plurality of fluid ejection nozzles having a first axial flow path length in the first nozzle plate layer. Applying a second nozzle plate layer to the first nozzle plate layer. Imaging and developing the second nozzle plate layer to provide a plurality of fluid ejection nozzles in the second nozzle plate layer having a second axial flow path length through the first and second nozzle plate layers, and removing a portion of the second nozzle plate layer adjacent to the plurality of fluid ejection nozzles having the first axial flow path length from the first nozzle plate layer.

Another embodiment provides a method for improving plume characteristics of fluid ejected from a fluid jet ejection head. The method for improving the plume characteristics of fluid ejected from a fluid jet ejection head includes: applying a first nozzle plate layer to a fluid flow layer on an ejection head substrate; imaging and developing the first nozzle plate layer to provide a plurality of nozzle holes having a first axial flow path length in the first nozzle plate layer; applying a second nozzle plate layer to the first nozzle plate layer; imaging and developing the second nozzle plate layer to provide a plurality of nozzle holes in the second nozzle plate layer having a second axial flow path length through the first and second nozzle plate layers; removing a portion of the second nozzle plate layer adjacent to the plurality of nozzle holes having the first axial flow path length; and ejecting fluid from the fluid jet ejection head through the plurality of nozzle orifices having the first axial flow path length and the plurality of nozzle orifices having the second axial flow path length.

In some embodiments, the first and second nozzle plate layers comprise laminated layers of photoresist material.

In some embodiments, the first nozzle plate layer is laminated to a flow feature layer for the ejection head.

In some embodiments, the first nozzle plate layer has a thickness in a range from about 5 microns to about 30 microns.

In some embodiments, the second nozzle plate layer has a thickness in a range from about 5 microns to about 30 microns.

In some embodiments, the plurality of fluid ejection nozzles having the first axial flow path length are adjacent to the plurality of fluid ejection nozzles having the second axial flow path length.

The fluid jet ejection device, the method of manufacturing an ejection head, and the method for improving the plume characteristics of fluid ejected from a fluid jet ejection head set forth herein have the advantage that the fluid jet ejection device can be used with a wide variety of fluids having different fluid characteristics. The fluid jet ejection device can be operable to provide a variety of plume angles by alternately or simultaneously activating the fluid injectors to eject fluid from fluid ejection nozzles having different fluid flow paths.

Drawings

FIG. 1 is a cross-sectional representation (not to scale) of a portion of a human nasal cavity and skull.

Fig. 2 is a cross-sectional view (not to scale) of a pharmaceutical drug delivery device according to an embodiment of the disclosure.

Fig. 3 is a schematic illustration of an ejection apparatus (schematic irradiation) showing a fluid jet stream and a droplet plume generated by ejection of fluid droplets from an ejection head.

FIG. 4 is a schematic cross-sectional view (not to scale) of a portion of a prior art jetting head.

FIG. 5 is a plan view (not to scale) of a prior art ejection head and nozzle plate showing details of a flow feature layer on a semiconductor substrate.

Fig. 6-9 are schematic illustrations of a process of manufacturing a jetting head according to an embodiment of the present disclosure.

FIG. 10 is a schematic cross-sectional view (not to scale) of an ejection head made by the process shown in FIGS. 6-9.

Detailed Description

For purposes of this disclosure, the following terms are defined:

a) Plume means a randomly oriented mist of fluid droplets with low inertia, affected by air resistance and air flow and possibly floating throughout the nasal cavity chamber for more uniform coverage;

b) The plume angle is a measure of the angle of the conical volume of the randomly oriented fluid droplet mist in the plume;

c) The plume height is a measure of the total height of the fluid droplet mist in the plume measured from the exit of the fluid ejection head to the total travel distance of the plume;

d) The fluid jet length is a measure of the length of the high inertia fluid droplet ejected from the exit of the ejection head to the apex of the plume angle;

e) Axial flow path length means the distance a fluid droplet travels through a nozzle orifice in a direction normal to a plane defined by the nozzle plate.

f) A pulse is defined as the number of times a fluid droplet is ejected from an individual nozzle. When a fluid ejector is energized by a series of voltage pulses of sufficient magnitude to eject fluid through an associated nozzle, a pulse of fluid may occur;

g) The pulse length is defined as the total number of times each pulse of each of the fluid ejectors is fired; and

h) The pulse delay is defined as the amount of time between individual pulses.

A schematic representation of fluid jet ejection device 100 is shown in cross-section (not drawn to scale) in fig. 2. The device includes a cartridge body 102 having a fluid outlet nozzle 104 attached to the cartridge body 102. A fluid jet spray cartridge 106 is disposed in the cartridge body 102. Fluid jet spray cartridge 106 contains the fluid to be dispensed by device 100. Logic board 108 is disposed in cartridge body 102 and is electrically connected to an ejection head 112 on fluid jet ejection cartridge 106 via logic board connection 110. As described in more detail below, the ejection head 112 includes a plurality of fluid ejection nozzles and associated fluid ejectors. A processor 114 is provided on the logic board 108 or on the ejection head 112 for executing control algorithms to control the ejection head 112 to modify the plume characteristics of the fluid ejected from the ejection head by controlling which fluid ejectors are activated. The cartridge body 102 may include a rechargeable battery 116 electrically connected to the logic board 108 for providing power to the ejection head 112. The power switch 118 is used to activate the device 100. A Universal Serial Bus (USB) input 120 may also be included to reprogram the processor for different pharmaceutical fluids. The activation button 122 may be used to activate delivery of a mist of fluid droplets according to the user's needs.

A wide variety of jetting heads 112 may be used with the apparatus 100 described above. Accordingly, the ejection head 112 may be selected from a thermal jet ejection head, a bubble jet ejection head, or a piezoelectric jet ejection head. Each of the foregoing spray heads may generate a fluid spray on demand and may be programmed to provide various fluid plume characteristics as described below. In contrast, conventional spray pumps are mechanically fixed for specific drug delivery applications and generally cannot be modified to provide various fluid plume characteristics.

Unlike conventional inkjet heads, which are designed to eject fluid droplets of 2mm to 3mm in a straight line to a substrate, such as paper, the apparatus 100 set forth herein is designed to further eject the fluid droplets as a mist into an air stream (air stream). When the fluid jet spray device 100 is used as a nasal spray device, the fluid droplet mist preferably lands in the mucosal area of the nasal cavity. FIG. 3 is a schematic illustration of a fluid jet spray device 200, the fluid jet spray device 200 having a spray head 202 for spraying fluid therefrom to form a relatively high velocity fluid jet stream 204 and a low velocity plume 206 of fluid floating on a stream of ambient air. The characteristics of the plume 206 (e.g., plume height PH and plume angle PA and fluid jet stream length JL may be affected by how the ejection head 202 operates, for example, a wider plume 206 may be the result of collisions between droplets as they are ejected from the ejection head 202. Another characteristic that affects the plume 206 is entrainment of fluid droplets from the ejection head 202. High velocity fluid droplets tend to create a gas stream perpendicular to the ejection head 202 that entrains subsequent droplets ejected from the ejection head 202 to further extract droplets from the ejection head 202. Accordingly, air entrainment may affect both the fluid jet stream 204 and the plume 206.

Without wishing to be bound by theoretical considerations, it is believed that the fluid velocity may affect the Plume Angle (PA). It is also believed that fluid drops traveling a longer axial flow path length through the nozzle orifice will have a lower drop velocity than fluid drops of the same size traveling a shorter axial flow path length through the nozzle orifice. Interactions between fluid droplets having different droplet velocities can cause a wider plume angle. The wider plume angle is believed to provide greater mist formation for fluid droplet impingement over a wider target area.

Referring to FIG. 4, a schematic cross-sectional view of an ejection head 300 is shown, the ejection head 300 having a single layer nozzle plate 302 attached to a flow feature layer 304, the single layer nozzle plate 302 having a thickness T. The flow feature layer 304 includes a fluid flow channel 306 for directing fluid from a fluid supply via 308 in a semiconductor substrate 310 to a fluid chamber 312. The fluid chamber 312 includes a fluid ejector 314 for ejecting fluid through a nozzle hole 316 in the nozzle plate 302. The axial flow path through the nozzle hole 316 is indicated by arrows 318, the arrows 318 being orthogonal to a plane defined by a surface 320 of the nozzle plate 302.

A plan view of the ejection head is shown in fig. 5, showing a plurality of nozzle holes 316 provided on both sides of the fluid supply through-hole 308. As described above, the fluid ejectors may be activated sequentially, alternately, or in predetermined groups to provide droplets of fluid for delivery to the nasal cavity. However, since all nozzle holes 316 of ejection head 300 have the same fluid path length, the fluid drop velocity of the fluid ejected by actuating fluid ejectors 314 using the same ejector actuation parameters will be the same. However, even if fluid injector parameters (e.g., frequency, pulse width, pulse length, or pulse delay) are modified, the range of modification of these parameters may not be sufficient to obtain the desired plume characteristics.

Accordingly, an ejection head is provided that includes a plurality of nozzle orifices having at least a first axial flow path length and a plurality of nozzle orifices having a second axial flow path length. As shown in fig. 6, an ejection head according to the present disclosure is fabricated by applying a first nozzle plate layer 400 to a flow feature layer 402 attached to a semiconductor substrate 404. The flow feature layer 402 is a photo-imageable material (e.g., a negative photoresist material), and the flow feature layer 402 is spin coated or laminated to the semiconductor substrate 404 prior to forming the fluid supply via 406 in the semiconductor substrate 404. Flow feature layer 402 includes fluid flow channels 408 for directing fluid from fluid supply through-hole 406 to fluid chamber 410, fluid chamber 410 including fluid ejectors 412 and may have a thickness in a range from about 10 microns to about 60 microns. Once the fluid chamber 410 and fluid flow channel 408 are imaged and developed in the flow feature layer 402, and the fluid supply vias are etched through the semiconductor substrate 404, the first nozzle plate layer 400 is laminated to the flow feature layer 402. The first nozzle plate layer 400 may have a thickness in a range from about 5 microns to about 30 microns and may be a photoimageable material (e.g., a negative photoresist material).

In the next step of the process, as shown in fig. 7, a mask 414 having opaque regions 416 and transparent regions 418 is used to image a nozzle aperture in first nozzle plate layer 400 having a first axial flow path length with actinic radiation (e.g., ultraviolet (UV) light, indicated by arrow 420). After imaging the first nozzle plate layer 400, the first nozzle plate layer is developed to provide nozzle holes 422.

In fig. 8, the second nozzle plate layer 424 is laminated to the first nozzle plate layer 400. Like the first nozzle plate layer 400, the second nozzle plate layer may be a negative photoresist material having a thickness ranging from about 5 microns to about 30 microns. Next, as shown in fig. 9, mask 426, which includes opaque region 428 and transparent region 430, is used to image nozzle hole 432 in second nozzle plate layer 424, second nozzle plate layer 424 having a second axial flow path length that is greater than the first axial flow path length of nozzle hole 422. Upon development of the imaged second nozzle plate layer 424, a portion of the second nozzle plate layer adjacent to nozzle holes 422 is removed by ejection head 434, as shown in fig. 10. Notably, as shown in fig. 10, the second axial flow path length L2 is greater than the first axial flow path length L1.

By combining one or more nozzle holes 432 having an axial flow path length L2 with one or more nozzle holes 422 having an axial flow path length L1, the interaction between liquid droplets ejected from the ejection head is increased, thereby forming a wider plume angle.

Nozzle apertures

432 and 422 may be adjacent to each other or on opposite sides of fluid supply through-hole 406 and may be activated simultaneously, sequentially, alternately, or in predetermined groups to create increased interaction between fluid droplets in the air stream.

The photoresist materials that may be used to make the first and second nozzle plate layers 400, 424 typically include a photoacid generator (photoacid generator) and may be formulated to include one or more of the following: a multifunctional epoxy compound, a difunctional epoxy compound, a relatively high molecular weight polyhydroxy ether, an adhesion enhancer, an aliphatic ketone solvent, and optionally a hydrophobic agent. For the purposes of this disclosure, "difunctional epoxy" means epoxy compounds and materials having only two epoxy functional groups in the molecule. "multifunctional epoxy resin" means epoxy compounds and materials having two or more epoxy functional groups in the molecule.

The epoxy component used to make photoresist formulations according to the present disclosure may be selected from aromatic epoxides (e.g., glycidyl ethers of polyphenols). An exemplary multifunctional epoxy resin is a polyglycidyl ether of a phenol formaldehyde novolac resin (e.g., a novolac epoxy resin having an epoxy gram equivalent weight ranging from about 190 to about 250 and a viscosity at 130 ℃ ranging from about 10 to about 60).

The multifunctional epoxy component may have a weight average molecular weight of from about 3,000 daltons to about 5,000 daltons as determined by gel permeation chromatography and an average epoxy group functionality of greater than 3 (preferably from about 6 to about 10). The amount of multifunctional epoxy resin in the photoresist formulation may range from about 30 weight percent to about 50 weight percent based on the weight of the dried photoresist layer.

The difunctional epoxy component may be selected from difunctional epoxy compounds including diglycidyl ethers of bisphenol-A, 3, 4-epoxycyclohexylmethyl-3, 4-epoxycyclohexenyl-carboxylate, 3, 4-epoxy-6-methylcyclohexylmethyl-3, 4-epoxy-6-methylcyclohexenyl-carboxylate, bis (3, 4-epoxy-6-methylcyclohexylmethyl) adipate, and bis (2, 3-epoxycyclohexyl) ether.

An exemplary difunctional epoxy component is a bisphenol-a/epichlorohydrin epoxy resin having an epoxide equivalent weight of greater than about 1000. "epoxide equivalent weight" refers to the grams of resin containing 1 gram equivalent of epoxide. The weight average molecular weight of the difunctional epoxy component is typically greater than 2500 daltons (e.g., from about 2800 to about 3500 weight average molecular weight). The weight of the first difunctional epoxy component in the photoresist formulation may be from about 30 weight percent to about 50 weight percent based on the weight of the cured resin.

Exemplary photoacid generators include a compound or mixture of compounds capable of generating cations (e.g., an aromatic complex salt, which can be selected from the group consisting of onium salts of group VA elements, onium salts of group VIA elements, and aromatic halide salts). Aromatic complex salts are capable of generating acid moieties (acid moieties) upon exposure to ultraviolet or electron beam radiation, which acid moieties initiate reactions with epoxides. The photoacid generator can be present in the photoresist formulations described herein in an amount ranging from about 5 weight percent to about 15 weight percent, based on the weight of the cured resin.

Compounds that generate protonic acid when irradiated with active rays (active ray) are useful as photoacid generators including, but not limited to, aromatic iodonium complex salts and aromatic sulfonium complex salts. Examples include bis- (t-butylphenyl) iodonium trifluoromethanesulfonate, diphenyliodonium tetrakis (pentafluorophenyl) borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, bis (4-nonylphenyl) iodonium hexafluorophosphate, [4- (octyloxy) phenyl ] phenyliodonium hexafluoroantimonate, triphenylsulfonium trifluoromethanesulfonate, triphenyl-sulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrakis (pentafluorophenyl) borate, 4' -bis [ diphenylsulfonium ] diphenylsulfide, bis-hexafluoro-phosphate, 4' -bis [ bis ([ beta ] -hydroxyethoxy) phenylsulfonium ] diphenylsulfide bis-hexafluoro-antimonate, 4' -bis [ bis ([ beta ] -hydroxyethoxy) (phenylsulfonium) ] diphenylsulfide bis-hexafluoro-phosphate, 7- [ di (p-tolyl) sulfonium ] -2-isopropylthioxanthone hexafluorophosphate, 7- [ di (p-tolyl) sulfonium-2-isopropylthioxanthone hexafluoroantimonate, 7- [ di (p-tolyl) isopropylsulfonium (pentafluorophenyl) sulfonium, 4-phenylcarbonyldiphenylcarbonylsulfonium-4 ' -t-butylphenyl-diphenylcarbonyldiphenylsulfonium hexafluorophosphate, 4' -diphenylcarbonyldiphenylcarbonyldiphenylthiocarbonate, 4' -diphenylcarbonylphosphonium hexafluorophosphate, 4' -diphenylthiocarbonate, 4-tert-butylphenylcarbonyl-4' -diphenylsulfonium diphenylsulfide tetrakis (pentafluorophenyl) borate, diphenyl [4- (phenylthio) phenyl ] sulfonium hexafluoroantimonate and the like.

The solvent used to prepare the photoresist formulation is a non-photoreactive solvent. Non-photoreactive solvents include, but are not limited to, gamma-butyrolactone, C _1-6 Acetates, tetrahydrofurans, low molecular weight ketones, mixtures thereof, and the like. The amount of non-photoreactive solvent present in the recipe mixture used to provide the nozzle plate layers 400 and 424 ranges from about 20 weight percent to about 90 weight percent (e.g., from about 40 weight percent to about 60 weight percent), based on the total weight of the photoresist recipe. The non-photoreactive solvent generally does not remain in the cured resin and is therefore removed prior to or during the resin curing step.

The photoresist formulation may optionally include an effective amount of an adhesion promoter (e.g., a silane compound). Silane compounds compatible with the components of the photoresist formulation typically have functional groups capable of reacting with at least one member selected from the group consisting of multifunctional epoxy compounds, difunctional epoxy compounds, and photoinitiators. Such adhesion promoters may be silanes having epoxy functional groups, such as 3- (guanidino) propyltrimethoxysilane, and glycidoxyalkyltrialkoxysilanes, such as gamma-glycidoxyalkyltrialkoxysilane. When used, the tackifier may be present in an amount ranging from about 0.5 weight percent to about 2 weight percent (e.g., from about 1.0 weight percent to about 1.5 weight percent), based on the total weight of the cured resin (including all ranges subsumed therein). An adhesion promoter, as used herein, is defined to mean an organic material that is soluble in the photoresist composition, which aids in the film formation and adhesion properties of the photoresist material.

Another optional component in the photoresist formulation that may be used for the nozzle plate layer includes a hydrophobizing agent. Hydrophobic agents that can be used include silicon-containing materials such as silanes and siloxanes. The hydrophobic agent is selected from heptadecafluorodecyltrimethoxysilane, octadecyldimethylchlorosilane, octadecyltrichlorosilane, methyltrimethoxysilane, octyltriethoxysilane, phenyltrimethoxysilane, t-butylmethoxysilane, tetraethoxysilane, sodium methylsilicate, vinyltrimethoxysilane, N- (3- (trimethoxy) propyl) ethylenediamine polymethylmethoxysiloxane, polydimethylsiloxane, polyethylhydrosiloxane and dimethylsiloxane. The amount of hydrophobic agent in

photoresist layers

400 and 424 can be from about 0.5 weight percent to about 2 weight percent (e.g., from about 1.0 weight percent to about 1.5 weight percent), based on the total weight of the cured resin, including all ranges subsumed therein.

Although the foregoing disclosure provides the nozzle plate layers 400 and 424 made of a photoresist material, the first and second nozzle plate layers are not limited to a photoresist material layer. Other materials, such as polyimide materials, may be used to provide the first nozzle plate layer 400 and the second nozzle plate layer 424 with specified axial flow path lengths.

It is noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless expressly and unequivocally limited to one referent. As used herein, the term "include" and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that may be substituted or added to the listed items.

For the purposes of the present specification and appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions used in the specification and claims, as well as other numerical values, are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

While particular embodiments have been described, presently unforeseen or unanticipated alternatives, modifications, variations, improvements, and substantial equivalents may be subsequently made by applicants or others skilled in the art. Accordingly, the appended claims as filed and as they may be amended are intended to embrace all such alternatives, modifications, variations, improvements, and substantial equivalents.

Claims

1. A fluid jet ejection device, comprising:

a cartridge body;

a fluid outlet nozzle attached to the cartridge body;

a fluid jet spray cartridge disposed in the cartridge body, the fluid jet spray cartridge containing a fluid and a spray head attached to the fluid jet spray cartridge; wherein the ejection head includes a plurality of fluid ejectors on the ejection head and a nozzle plate having a plurality of fluid ejection nozzles therein associated with the plurality of fluid ejectors, wherein a first portion of the plurality of fluid ejection nozzles have a first axial flow path length and a second portion of the plurality of fluid ejection nozzles have a second axial flow path length greater than the first axial flow path length.

2. The fluid jet ejection device of claim 1, wherein the second axial flow path length is provided by a second nozzle plate layer attached to a first nozzle plate layer.

3. The fluid jet ejection device of claim 2, wherein the first nozzle plate layer has a thickness in a range from 5 microns to 30 microns.

4. The fluid jet ejection device of claim 2, wherein the second nozzle plate layer has a thickness in a range from 5 microns to 30 microns.

5. The fluid jet ejection device of claim 2, wherein the first nozzle plate layer is laminated to a flow feature layer for the ejection head.

6. The fluid jet ejection device of claim 2, wherein the first and second nozzle plate layers comprise laminated photoresist material layers.

7. The fluid jet ejection device of claim 6, wherein the first nozzle plate layer is imaged and developed to form the first portion and the second nozzle plate layer is imaged and developed to form the second portion.

8. A method of making an ejection head, comprising:

providing a semiconductor substrate having a plurality of fluid ejectors thereon;

applying a fluid flow layer to the semiconductor substrate;

imaging and developing fluid channels and fluid chambers in the fluid flow layer;

etching a fluid supply via through the semiconductor substrate;

applying a first nozzle plate layer to the fluid flow layer;

imaging and developing the first nozzle plate layer to provide a plurality of fluid ejection nozzles having a first axial flow path length in the first nozzle plate layer;

applying a second nozzle plate layer to the first nozzle plate layer;

imaging and developing the second nozzle plate layer to provide a plurality of fluid ejection nozzles in the second nozzle plate layer having a second axial flow path length through the first and second nozzle plate layers, and removing a portion of the second nozzle plate layer adjacent to the plurality of fluid ejection nozzles having the first axial flow path length from the first nozzle plate layer.

9. The method of manufacturing an injector head of claim 8, wherein the first nozzle plate layer has a thickness in a range from 5 to 30 micrometers.

10. The method of manufacturing an injector head of claim 8, wherein the second nozzle plate layer has a thickness in a range from 5 microns to 30 microns.

11. The method of manufacturing an ejection head of claim 8, wherein the first nozzle plate layer is laminated to the fluid flow layer.

12. The method of manufacturing an ejection head of claim 8, wherein the second nozzle plate layer is laminated to the first nozzle plate layer.

13. The method of manufacturing an ejection head of claim 8, wherein the plurality of fluid ejection nozzles having the first axial flow path length are adjacent to a plurality of fluid ejection nozzles having the second axial flow path length.

14. A method for improving plume characteristics of fluid ejected from a fluid jet ejection head, comprising:

applying a first nozzle plate layer to a fluid flow layer on an ejection head substrate;

imaging and developing the first nozzle plate layer to provide a plurality of nozzle holes having a first axial flow path length in the first nozzle plate layer;

applying a second nozzle plate layer to the first nozzle plate layer;

imaging and developing the second nozzle plate layer to provide a plurality of nozzle holes in the second nozzle plate layer having a second axial flow path length through the first and second nozzle plate layers, and removing a portion of the second nozzle plate layer adjacent to the plurality of nozzle holes having the first axial flow path length; and

ejecting fluid from the fluid jet spray head through the plurality of nozzle orifices having the first axial flow path length and the plurality of nozzle orifices having the second axial flow path length.

15. The method for improving plume characteristics of fluid ejected from a fluid jet ejection head of claim 14, wherein the first nozzle plate layer has a thickness ranging from 5 microns to 30 microns.

16. The method for improving plume characteristics of fluid ejected from a fluid jet ejection head of claim 14, wherein the second nozzle plate layer has a thickness ranging from 5 microns to 30 microns.

17. The method for improving plume characteristics of fluid ejected from a fluid jet ejection head of claim 14, wherein the first nozzle plate layer is laminated to the fluid flow layer.

18. The method for improving plume characteristics of fluid ejected from a fluid jet ejection head of claim 14, wherein the second nozzle plate layer is laminated to the first nozzle plate layer.

19. The method for improving plume characteristics of fluid ejected from a fluid jet ejection head of claim 14, wherein fluid is ejected from the fluid jet ejection head by ejecting fluid through the plurality of nozzle holes having the first axial flow path length and the plurality of nozzle holes having the second axial flow path length alternately or simultaneously.